Cam mechanism



Patented June 30, 1931 1 UNrrEo ,STATES JOHN ca PATENT OFFICE i DAL'roN, or I IJIa.IaA 1vI,NORTE: CAROLINA,` AssIeNOR or omi-HALF 'rd p. RICHARD II. WRIGHT, 01j IIURHAMf-NORTII- CAROLINA CAM MEGIIANISII Application led October 25, 1927. Serial Zlo. 228,627...

The present invention relates to cam mechanism of the class embodying a cam or cams and cooperating cam roller Vor r'ollers, and the object of the-invention is to provide novel andimproved means for lubricating the cam roller or rollers 'of suchv cam mechanism,whereby the same will be enabled vto operate I,continuously at r'elatively high speeds without overheating or rapid wear due to friction. A

In the accompanying drawings Fig 1 represents a transverse section through a cam mechanism embodying the improvements provided by the present, invention; Y

Fig. 2 represents a section `taken on the line 2 2 of Fig. 1;

Fig. 3 is a .viewvof the cam roller mechanism and its support andr the cam Vroller lubricating means; and

Fig. 4 is a top plan view of the structure shown in Fig. 3. L

Similarparts are designated by thepsame reference characters. in the several figures.

AThe invention in the present instance is showny applied to the cam mechanism for operating the. loopers of over-seaming sewing machines of the general type shown and described` in Patent No. 591,049, granted Oct. 5, 1897 to J. N. Merrow and the patents referred to therein, and Patent No. 733,760, granted July14, 15903 t'o W. H. Stedman,

referenceA being made to those patents for a, more detailed disclosure forthe construction and inode of operation ofgmachines of this class. For thepurpose of anexplanation of the present invention, it is believed to be sufficient to describe the parts of the machine shown as comprising a main frame or housing 1, which has main and countershafts 2 Yand 3 journalled in its Aupper portion, the lower portions of these shafts being contained in a chamber 4 formed within the housing, and cams 5 and 6 are fixed on the main and countershafts respectively. The cams are formed-or provided with gear portions 7 and-8 which mesh andA thereby cause the countershaft to be driven 'from'.the main shaft'and insu're rotation of thefcams in unison. 'The cams are of the cylindrical type,A and each cam is formed with an appropriately shaped cam groove 9 which extends around its circumference.

The cams as shown serve to actuate -a reciprocatory lower looper 10 which has an eye 11 therein throughwhich the'looper thread passes, and to also actuate an oscillatory upper looper 10a, the lower looper 10 being secured in a slide 17 while the upper looper'lO is secured 'in an arm 13 which is a part of a rocker or carrier 14, the latter having oppositely extending arms which carry rollers 15 which ride in the rooves 9 of the respective cams. In oper'at1on,`the rocker or carrier 14, due to the contour of the ycam grooves 9, has both reciprocatory and rocking motions while the slide has a reciprocatory motion, and for this reason the rocker is pivoted on the slide 17 z by a trunnion.16 which is carried by the'rocker and has a bearing in the slide, the slide being guidedy to reciprocate in a dovetail groove 18 formed in a frame cap or cover plate 19, the latter being removably secured to a side ofthe frame or casing 1.

Each cam roller 15 is shown as made up of a plurality of roller sections which are alined axially and arranged to bear respectively on portions of the working face of the cam groove which are located at differentradial distances from the center of the cam, and the components or sections of the cam 'roller are capable of revolving independently and at different speeds on a common journal pin 2O which is fixed in theirocker 14.

In order to adequately lubricate the bearing surfaces between the roller sections and and their journal pins, and, thereby avoid over-heating and excessive wear of these bearing surfaces when the cam mechanism is' operated continuously a't high speeds, means is provided for supplying oil or other lubricant directly to the cam rollers. Such means consists preferably of a pair of plates V21 andl 22.. which are @secured to the inner side `of'the frame' cap or cover plate 1:9 at opposite sides ofthe slide *17 and these plates are formed with pointed lips 23 and 2 4 which are offset inwardly to bring them into position in alinement with the respective cam rollers 15. Assuming the cam mechanism to be mounted in a position 'which brings the axes of the cams in vertirespective cam rollers. The motions of the" cam rollers beneath the lips 23 and 24 will be approximately vertical so that the cam rollers will always be in osition to receive oil or lubricant dropping rom the respective lips 23 and 24. The oil or lubricant may be supplied to the plates 21 and 22 by oil lead pipes 25 and 26 respectively, these oil pipes being open to receive a supplyL of oil or lubricant from an oil can or t e like, and the lower ends of these oil pipes extending inwardly through the casing 1 and arranged to discharge oil or lubricant there from on to the upper edges of the plates 21 and 22 respectively. Additional oil lead pipes 28 may be arranged between the pipes 25 and 2G, the lower ends of the pipes 28 leading to the upper edge ,of the frame cap or plate 19 at the opposite sides of the dovetailed groove 18 in which the slide 17 reciprocates, the oil or lubricant supplied through the pipes 28 serving to lubricate the slide 17 and its guiding roove.

In order to furt er reduce friction between the working surfaces of the cams and their cooperating rollers and to consequently reduce or avoid tendency of the cam rollers to become heated or to wear unduly, each cam is provided with a suitable number of oil leads 29 which extend therein parallel to the axis of rotation of the cam and are suitably spaced around said axis. As shown in Figs. 1 and 2, a set of four of these oil leads is provided, and ducts 30 extend from the lower ends of these oil leads outwardl to the rear surfaces of the cam groove 9. Il, will be noted in Fig. 2 that the ducts 30 lead to the upper or the lower surface of the cam groove 9, according to the location of the cam groove surfaces upon which the pressure or thrust between these surfaces and the cam roller occurs, the ducts 30 serving to conduct oil or lubricant from the vertical or axial leads 29 outwardly to the wear surfaces of the cam, and the flow of the oil or lubricant through the ducts 30 being aided by centrifugal force developed by the high speed rotation of the cam. Other ducts 31 lead from the lower ends of the oil leads 29 to the lower end of the cam, for

is formed inthe upper end of the cam around the shaft, the bottom of this well preferably sloping downwardly, as Iis shown 1n Fig. 2, and the outer circumference of the well communicates with the oil leads 29 through radial ducts 35, centrifugal force developed by the high speed rotation of the camacting to insure feed of oil or lubricant from the well to the vertical oil leads 29. Oilfoi' lubricanty is supplied to the well 34 through a pipe 36 which is extended into the casing 1 and has its inner end threaded into a bearing 37 in which the upper end of the respective cam shaft is journalled, the inner end of this pipe communicating with a duct 38 which is formed in the lower end of the bearing 37 along side of the shaft, this duct extending from the inner or outlet end of the ipe 36 downwardly to a point directly a ove the well 34, gravity serving to conduct the oil or lubricant from the pipe 36 to the well 34. Each pipe 36 may be supplied with oil or lubricant from a sight feed oiler 39 as shown, or from any other suitable source of supply..

The block 74 to which the usual trimmin knife 75 and an agitating finger 73 are fixed may be reciprocated by a yoke 76 pivoted to the lower end of the casing 1 at 77 and con- 1 taining a slide block 78 with which an eccentric 79 formed on the lower end of the cam 5 coo erates. The slide 78 and eccentric 79 will e supplied with adequate lubricant through the ducts 31 which lead to the lower end of the respective cam and are supplied with lubricant in the manner hereinbefore described. l

1. The combination with a pair of cams having circumferential cam grooves, and a member having rollers cooperative with the grooves of said cams and reciprocated vertically thereby, of a pair of oil dripping li s located above the respective rollers in su stantial alinement with their directions oi.

motion.

2. The combination with a pair of cams having circumferential cam grooves, a member having rollers cooperative lwith the grooves of said cams and reciprocated vertically thereby, and a vertical slide supporting said member, of li s located above the' respective rollers for ropping oil thereon, and, means for supplying oil to the upper end of said slide.

In testimony whereof I have hereunto set my hand.

JOHN T. DALTON.

the lubrication of the lower bearing 33 for ithe shaft of this cam and also other parts below the cam, as will hereinafter appear. Oil or lubricant is distributed equally to the oil leads 29 from an annular well 34 which 

